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820-4924-a doesnt turn on - chimes
- Thread starter MegaObi
- Start date
All the iCore MacBooks start directly when charger is connected; if no battery present.
Check for USB activity.
Also try PRAM reset.
Check for USB activity.
Also try PRAM reset.
Hey informaticos. please excuse me, i re-read your post again. I solder the wire smc_onoff_l and i touch to ground for 1 sec. i was holding for longer before with tweezers.
so i get pulse on Pm_pwrbtn_l
but NO pulse on:
pm_slp_s5_l
pm_slp_s4_l
pm_slp_s4_btmux_l
pm_slp_s3_r_l
pm_slp_s3_l
pm_slp_s3_buf_l
pm_slp_s0_l
i also try pram and there is USB activity
so i get pulse on Pm_pwrbtn_l
but NO pulse on:
pm_slp_s5_l
pm_slp_s4_l
pm_slp_s4_btmux_l
pm_slp_s3_r_l
pm_slp_s3_l
pm_slp_s3_buf_l
pm_slp_s0_l
i also try pram and there is USB activity
I don't understand what you do there.
Impossible to have S3/0 voltages if you don't even get a pulse on PM_SLP_Sx_L signals.
Do you get all them steady high level?
I asked for pulse supposing all stay low...
Impossible to have S3/0 voltages if you don't even get a pulse on PM_SLP_Sx_L signals.
Do you get all them steady high level?
I asked for pulse supposing all stay low...
Ok, so MLB is powered up, even CPU.
Can you confirm USB activity with OSX pendrive with Link LED?
If flashes, there is USB activity for sure.
Disconnect internal SSD.
Can you confirm USB activity with OSX pendrive with Link LED?
If flashes, there is USB activity for sure.
Disconnect internal SSD.
Do you get 5V at pins 28-30 of J8300, at least in the first few seconds?
It should, even without LCD.
If LCD is connected, LCD_HPD_CONN should rise to 2.5V and DP_INT_HPD to 3.3V.
If not, 5V will drop too from J8300.
It should, even without LCD.
If LCD is connected, LCD_HPD_CONN should rise to 2.5V and DP_INT_HPD to 3.3V.
If not, 5V will drop too from J8300.
If you get steady 5V there, means LCD is recognized.
You should get image at least; check with torch from backside.
Do you get any voltage at pin 1/J8300?
I recommend to test with known good LCD assembly (compatible).
You should get image at least; check with torch from backside.
Do you get any voltage at pin 1/J8300?
I recommend to test with known good LCD assembly (compatible).
Do you get voltage at pins 11 & 17 of U7700?
Check F7700 and R7731/32.
Can you confirm image?
Check F7700 and R7731/32.
Can you confirm image?